1. Field of the Invention
The present invention relates to an endoscope with a sealed housing wall and an element configured therein, the element being adjustable by a drive element affixed thereto.
2. Description of Related Art
Endoscopes of the aforementioned type are fitted with means which, within a sealed housing wall, must be protected against environmental factors. Such means, in particular, are imaging devices such as lens optics or an electronic camera, light transmitting elements such as fiber optics or other sensitive optical or an electronic devices. Such devices are protected in the space enclosed by the sealed housing wall from ambient humidity and vapors.
Endoscopes of this kind already are used medically, the housing protecting against body fluids, cleaning and sterilization.
Component displacement is implemented using magnetism applied across the nonmagnetic housing and, therefore, does not require applied sliding motions or other elements that might jeopardize the sealing of the housing. As a result, the housing is well sealed and, in particular, such housing also allows very frequent steam autoclaving for complete sterilization.
The displaceable component may be used to drive electrical switches within the endoscope, to switch valves, for instance, for aspiration or rinsing lines and, in particular, to adjust optics for instance to focus them.
Endoscopes of this kind are known from the German patent documents A1 197 13 276 and A1 195 21 654. In these designs the drive means also is in the form of a permanent magnet. In the case of the design of the first document, several pairs of inner and outer magnets are used for the purpose of attaining an exact angular coupling. The ring magnetically rotated on the inside engages a displacement thread and, in this manner, is secured by friction. In the design known from the latter document, an inner magnet slides within a curved path which, again, is intended to secure it by friction. The purpose is to prevent the component from shifting when impacts should disengage the inner and outer magnets. However, such designs do not allow precise setting of the components because the inner magnet may stop at any position.
The known designs require mounting the magnet permanently on the endoscope. The adjustment component which, for that purpose, is present at the endoscope and which contains the magnet however also entails interstices and gaps between the adjustment component and the endoscope, and these interstices and gaps are difficult to access, to clean and to sterilize.
Because the adjustment component must always remain at the endoscope, even when not needed for adjustment, it may interfere with handling the endoscope and will add to its weight.
Furthermore, such an adjustment component may only be mounted on the main body and only may drive components within the main body. In the region of the endoscope""s stem, that is in particular at the optical objective present at the stem""s distal end zone, the state of the art will not allow adjustments because external adjusting means permanently affixed to the stem are precluded.
It is an object of the present invention to create an endoscope of the above discussed species that is free of external adjusting devices.
In the invention, the component is mechanically secured in given adjustment positions predetermined by design and it may be magnetically displaced using the force of a magnet overcoming the retention force of the securing element. The externally acting magnet is mechanically separate from the endoscope and need be brought into magnetical interaction only when adjustments are required. The externally acting magnet may be removed thereafter without endangering the new adjustment position of the component, which is held by the securing element. The endoscope, therefore, may be put to use without being hampered by an external adjusting means. This design moreover allows situating the component to be adjusted in the endoscope""s stem zone, especially in the optical objective zone, which was heretofore unknown.
Illustratively, the securing element may be a friction brake securing the drive component""s position and supplemented by a limit stop allowing precise position adjustment. Magnetic securing elements also are possible to constrain specified positions. Preferably, however, spring-loaded detent elements represent simple implementations to secure the component into specified positions.
The present invention also allows handling and/or adjustment of the optic objective at the distal stem zone. Required objective adjustments may be carried out there, for instance, focusing by axially displacing elements of the objective. Preferably, however, the present invention will also permit the endoscope""s viewing direction to be adjusted. This feature is the answer to the surgeons"" long-held hope, namely to change in simple manner the viewing direction, for instance from straight ahead to obliquely. This change does not entail a change of endoscope, merely with a brief stop in the surgical procedure, movement of a magnet permits an adjustment in the vicinity of the distal endoscope tip is made.